Devil of the Night Sky
by Xamusel - Gamma 11
Summary: *Idea partially given by Takeshi Yamato* When Issei was only a seven year old, he finds a book in the park the same day the old man was telling the pervy story. When he picked the book up, he never expected such a difficult life ahead of him... nor did he expect to have guardians that would stay with him all throughout his days alive. But, wait, what happened to him!


**Disclaimer:** I do not own the franchises involved in this story. Thank you for understanding.

 **Xamusel: Alright, another crazy idea came into being because of Takeshi Yamato, this time… *looks at the above information* do I** _ **really**_ **have to spell it out for you? Now, I'll be writing this story, but that's not to say that Takeshi won't help with that… unless he doesn't want to. That's a problem there that I'd rather avoid if possible.**

 **Now, the basic premise of the idea goes "What if a member of the Rias team that canonically happens becomes the Master of the Tome of the Night Sky", and I decided to expand upon it a lot more than that. If you want to know what I mean… well, like everyone else, just wait and see. :)**

 **EDIT 12/25/2017: …well, I was a big idiot the first time around, bar none. I did a specifically stupid thing in these notes before I decided to go back and add more content. Please forgive me for that. Anyway, these notes are representative of that change, now and forever.**

 **In any case, this edited prologue will be my chance to fix things for the whole story, by a long shot. I had no idea where I was going with it originally, but now, I have that idea. I'm not going to spoil what that idea is for you guys… not at all.**

 **Here we go, then… now that that's out of the way, I plan to get this story rolling out. With that said… Can't Escape From Crossing Fate! FIGHT!**

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 **Devil of the Night Sky**  
 _Story by Xamusel_

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Prologue: The Tome That Changed Everything

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 _Kuoh Central Park_

 _Kuoh Town_

 _Japan_

 _Non-Administrated World Number 97_

 _1345 Japan Standard Time, April 2nd, 2002_

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Hyoudou Issei was a boy who wanted to be a hero, as he promised a friend that moved away the previous year. When he was six years old he and his friend Irina-kun, who insisted that he was a girl for some reason, were always playing heroes and spell casters; pretending that there was such a thing as the supernatural. Ah, the fun the two of them had, as well as the brawls they got into with bullies who picked on those weaker than they were… okay, that last part was decidedly _not_ fun, but who cares?

Right now, Issei was sitting on a park bench and partially looking at a scene in the park that was unfolding… an old man was doing some weird things with his hand, and a lot of children were enraptured by the show the old man was putting on. Issei was paying only half a mind at most to the old guy at the moment, somewhat distracted by something that he thought he saw in the bright sky up above, in front of the sun to be precise.

Normally, a person would be blinded by the sun when looking at it, but Issei was careful to have his eyes adjusted to the light. It was either that, or he was bound to be in trouble during gym class, which he didn't want to have happened. Still,… there was something that seemed to be coming down from the sky, or so Issei was led to believe, and, if he calculated the speed and trajectory right, it would land in the park in only a few moments!

Yes, Issei was a genius mathematician for his age group, and he was _damn_ proud of it! Still, there were times when he wished he was oblivious to his talent, like right—

*CLOCK!*

—now? Issei looked at the group of children listening to the old man, who were shocked for a few seconds before they ran away in fright. He then looked at the old man, who was knocked out face first because of the object landing on his, apparently, thick skulled head.

' _Huh,'_ Issei thought. _'I guess Newton's Third Law of Physics applies to everything… wait, is that a_ book _, or am I imagining things?'_

When he looked at the object in question, blinking his eyes a few dozen times and pinching his cheeks twice each, he realized that, no, he wasn't imagining things. There was a legitimate _book_ on the back of the old guy's head! Normally, Issei would be freaked out by that, but he wasn't for some reason.

The book was brown, with a cross shaped symbol on the front cover. It also looked rather thick. But the most noticeable detail was that it was bound with what looked like thick chains.

Issei walked to the book, being careful to avoid the other children in the process, a stick in hand to poke the book with if need be. He didn't know how come the book had survived falling through the sky, as that made things burn when doing so, last he checked.

Finally, he got to the book, the old guy underneath it barely even twitching. He stopped a couple feet away from the book, deciding then and there to poke it with the stick first to see if it was safe. He raised the stick and proceeded to poke the book once.

No reaction from poking the book with the stick.

He then tossed the stick aside, moving to pick up the book with his hands. Before he could actually _touch_ the book, however, a police siren was heard headed in his exact direction… wait, was he in _trouble_?!

Panicking slightly, Issei was about to bolt for it when he remembered that he wasn't in trouble, simply because he was looking at what happened in the daylight sky. He wasn't even _near_ the old guy when the book collided with the geezer! As such, he was fairly certain that the police weren't here for him, anyway.

He saw the police car stop outside the park, a pair of police officers scrambling out to apprehend someone, who was… in the park? Issei was confused about what was happening.

"Where's the pervert?!" the senior of the two roared in question.

Issei blinked in surprise. _'Per… vert?'_ He thought. _'What does_ that _mean?'_

An adult in the park, someone who Issei didn't remember meeting before, answered, "Laying on the ground, out cold because an object collided with his head from behind! There's a kid who was poking the object with a stick, officer, although…"

The junior officer raised a hand up to forestall conversation. "We understand," he said, before turning to the man knocked out by the book. He walked over to the man and placed a pair of fingers on the old guy's neck. "He's breathing," he announced, "barely. What do we do, Captain?"

The captain looked at Issei, a serious gleam in his eyes. "Kid, could you explain what happened here?" he asked Issei.

"Um, well," Issei started, before he sucked in a breath of air and released it, calming himself down a bit. "I was on the park bench over there," he continued, pointing at the bench in question. "As I was sitting, I was partially paying attention to what was going on here, mainly confused by what I saw up in the sky. I saw an object fall at terminal velocity towards this park, and—"

"Kid, isn't that an awfully big phrase for you to say?" the junior officer asked Issei. "I don't think they teach about terminal velocity in elementary school, do they?"

Issei chuckled sheepishly, scratching the back of his neck. "I was gifted to understand math that well," he admitted. "Anyway, the object turned out to be the book that landed on the man's head, and it's still intact."

The junior officer looked at the book and raised an eyebrow. "How did a book fall from the sky and survive completely intact?" Turning to face Issei, he saw the raised shoulders and sighed. "Well, I guess you're now the owner of this book, I think." Standing up, he picked up the old guy and dragged him away from the area, the book falling off of the geezer's head, landing on the ground. "We book the old guy, Captain?"

The captain gave a deep sigh of his own. "Might as well, lieutenant," he said. "Although, the kid might want to find his parents soon and go home. Don't want anyone to nab him at all."

Issei nodded in relief, before he grabbed the book and took off to find his parents, unsure of how to share the details of what happened just then. He ran to the place where they parked the car… and stopped a few feet away, looking confused by what he was seeing, or, in this case, _not_ seeing.

He didn't see his parents car.

Instead, he saw an empty spot that was devoid of anything there, even in the rest of the spots around his parents spot at the park. What shocked Issei was that he was alone… possibly without his parents coming to get him. It didn't seem fair for him to be alone… wait, he heard a car drive on in. Looking in the direction the noise came from, he saw that his parents were back.

When the car parked, Issei was quick to get to his seat and buckle up. "Okaa-san, otou-san, I saw something strange happen today!" he exclaimed to his parents when everything was ready.

"Oh?" Issei's mother, Megumi Hyoudou, asked. "What something was that?"

"A book fell from the sky and landed on an old man's head!" Issei answered, still exclaiming his words. "I have the book on hand to prove it, too!"

"Whoa, Issei, calm down," Issei's father, Yuichi Hyoudou, chided him with a playful tone. "How can a book fall from the sky without burning up?"

" _Exactly_!" Issei continued to exclaim. "It _should've_ , but it _didn't_! That's the weird thing!"

Megumi pondered what was said, before she asked, "You said you have the book with you, right?"

"Yeah, okaa-san," Issei answered, moving the book to hand it to his mother. "Here you go."

"Thanks, Issei," she said as she grabbed the book. Taking a look at the book, she felt a residual trace of heat coming off of it, lending credence to Issei's story. "Hmm… I feel you aren't lying about this, dear," she said as she returned the book to him. "It's rather faint, but I could feel the heat, Issei."

"Really? You believe me?" Issei asked, hope in his eyes as he took the book back into his possession.

"You sure, Megumi?" Yuichi asked his wife, turning to face her while driving. This was also the last time either of Issei's parents said a single word, as a semi-truck ran right into the front half of the family car from the driver's side.

The last Issei saw of his parents was the sheer shock of what happened, plus the debris of the car piercing them in different vital spots, killing them instantly and splattering blood on him and the book in his possession. He was lucky that he was in the back seats and buckled up in an over the shoulder seat belt… otherwise, he'd have joined them, too. As it stood, however, he hit his head on the window next to him and was knocked out.

The last thing he heard was a regal feminine voice saying in what sounded to be German, yet clearly recognizable to him somehow, "Bereithalten, Meister des Nachthimmels. Erwache deine wahre Gestalt."

' _Wait… I'm the Master of the Night Sky?'_ Issei thought in surprise. _'What does_ that _mean?! And awaken my true form? What is the voice_ talking _about?!'_ Unfortunately for him, he wouldn't know what the voice was referring to until later, as he was knocked out until hours after the paramedics arrived. As it stood, however, the book vanished from sight when the paramedics were about to save him from the wreckage.

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Mere moments after the accident, a black haired, black eyed man in a tattered black cloak that covered everything below his neck floated in the air above the car that the Hyoudou family was in, observing the spot where Issei was in the back.

…okay, he was actually using an Astral Projection to do so, but the idea was the same.

Anyway, the point was, this man could easily tell that something was going to happen in the future that required his attention to manipulate. It was a very rare situation where he had almost literally _no_ idea what his plan should even be… but, in spite of the odds, he was in such a situation.

' _Hmm…'_ The man thought. _'Is there any chance I can adjust this situation to match my goals?'_

It took him less than a thousandth of a second, but he calculated the total risks of fifteen options that came to mind, almost as if he were a robot… which, while wrong, was _not_ a false comparison. The reason why he calculated the total risks of those fifteen options was because of one of his abilities as a supernatural being… he could see the future of practically anything he wanted to, based on what he caused, and the effect it had on any particular timeline. Of course, this ability was supposed to be limitless, but that didn't mean that he could see _everything_ … if anything, it was just _really_ difficult to create a future that he _couldn't_ foresee.

One of these possible future endings was what he was going to bank on… in most of those futures, Issei would activate the book and get his Knights from it, but he would have no impact on the fate of the world. In fact, the world would die _long_ before the universe could be reshaped, which threw _everything_ for a loop. That accounted for ten of the possible options that he could enact for the future.

To elaborate, option one, without any meddling whatsoever, was Issei treating the knights as a simple family, not wanting them to fight at all. Option two would be getting him to want to use the book to bring back his parents. Option three was making him somewhat curious about the book, trying to look into its history to see why it was commonly called the 'Book of Darkness'. Options four through seven involved causing him to fall in love with Vita, Signum, and/or Shamal. Option eight made him completely indifferent to the Wolkenritter. Option nine made him outright hostile to them. And last, but certainly not least, option ten made him want to get rid of the book, but had him going about it the wrong way.

Options eleven through thirteen were more tricky to work with. They involved the book being absent from Issei, giving the boy access to a draconic gauntlet and (eventual) form, but also making him a servant to a being that was super… clingy, to put it very, _very_ lightly (no, not Yandere, thank goodness for _that_ ). The fate of the world would be on the brink of destruction by means of a monster called Trihexa in the outcomes of each option, but the monster would be destroyed when he, the man observing the scene in the here and now, prepared to reshape the universe with his ally and best friend.

Option eleven involved turning him into a contract mage, one that could amplify his spells with said draconic gauntlet, for until the time came to turn him into the servant of said clingy being. Option twelve involved turning him into a clergyman's apprentice until being told that the Biblical God was dead (the man had to hold back a laugh… that was a lie of the highest order created by a being named Rizevim). As for option thirteen… well, keeping him in his normal life without making him a mage or member of the church was ridiculous, since it would've worked better if he had his parents with him. _That_ hardly had any possible futures in it whatsoever.

Option fourteen was… okay, _that_ was a positively evil idea, turning Issei into a member of the LDO. It would ensure that he started training in how to possibly become a Hadou God of his own right, if Issei was able to manipulate the book _and_ his gauntlet to an insane degree. However, none of the futures showed that he could, especially going down that road. It also had the risk of destroying all the members of the LDO's higher echelons… yes, including himself, what with the war that would be waged with an organization called the Time-Space Administration Bureau.

Option fifteen was… well, the safest option, and the one with the possible future he was banking on. It had Issei becoming a mentor to someone and going off-world forever as part of the ripple effect, while at the same time making sure he had safely fixed the book _and_ kept the gauntlet. The option in question was forcibly awakening the gauntlet while causing the book to be in sleep mode for a number of years. The first ripple he wanted that was caused by said option would involve Issei going to the hospital while smuggling in the book with its Knights waiting to make themselves known. Then the second ripple would involve him finding someone a number of years later to take care of as a surrogate older brother… and so on and so forth.

It took a teensy bit of effort, as in less than one one-hundredth of a percent of effort, but the man went with option fifteen. It was very fortunate that, a few minutes later, the nearest ambulance came on by.

"Genau nach Plan," the man said, before his Astral Projection faded from the area.

If only he realized that there was a _separate_ ripple that would happen in the time before Issei woke up…

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Translation Notes: Bereithalten, Meister des Nachthimmels. Erwache deine wahre Gestalt = Standby, Master of the Night Sky. Awaken your true form.

Genau nach Plan = Just as planned.

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 **Xamusel: FINISH!**

… **okay, this is a good place to stop for now. I hope that you all enjoy the redone Prologue, at least based on what I had to do to get it fixed up. Of course, I had modified the plot, like I** _ **believe**_ **I mentioned I would do. I am hoping that, if you want to call the good guys OP, you remember that it's just an incredibly** _ **small**_ **fraction of what the bad guys are able to do.**

 **Oh, right, if anyone remembered the prior version of the above notes, I should've said that the translation guy was named Donar,** _ **not**_ **Doran. I want to thank him for the translations.**

 **I also want to thank Takeshi Yamato for the idea… as a matter of fact, please get to writing your revised note right below this, man.**

 **Takeshi Yamato: OK, I'm not going to be doing too much here - mainly just a beta role and idea sounding board, with some suggestions of my own. If Xam needs help with some of the MGLN elements, I'll do what I can there.**

 **That said, this definitely looks like it'll be fun, and we need more MGLN crossovers anyway.**

 **Xamusel: Thanks, Takeshi, I'm glad you could write that.**

 **Until we meet again… farewell,  
Xamusel**

 **PS: I was** _ **going**_ **to rewrite the whole thing from the ground up, but I didn't have much of a desire to pull that off, so I decided to do it this way. I hope that you all don't mind.**


End file.
